In the preparation of paper, woven support belts are used for the initial casting and subsequent treatment of the paper. These belts are known as paper clothing. A variety of materials has been used in the manufacture of such belts, including metals and, more recently, thermoplastic monofilaments. Thermoplastic materials which have been used in the weaving of these belts include nylon as well as polyester monofilaments.
A continuing problem in the preparation of paper-making belts is providing a belt having an acceptable balance of dimensional stability and flexibility. A variety of techniques has been proposed, including the use of thermoplastic monofilaments having different degrees of orientation in the machine and transverse directions, as described in Curtis et al. U.S. Pat. No. 3,915,202. However, previously proposed techniques have often failed to provide the desired balance between dimensional stability and flexibility, or resulted in a woven belt which became brittle after a relatively short period of service.